Lipid peroxidation and antioxidant activities in rat testis after chronic cocaine administration

Objectives, Our recent study has shown that cocaine has adverse action on s permatogenesis and fertility in male rats. Adverse effects of cocaine on th e testes may be mediated by oxidative damage and subsequent lipid peroxidat ion. Glutathione is a cellular antioxidant and is found in high concentrati ons in the rat testes. In this study, the effects of chronic cocaine admini stration on the activities of glutathione peroxidase, the level of testicul ar reduced glutathione, and lipid peroxidation were investigated. Methods, Thirty-day-old male Sprague-Dawley rats were given cocaine hydroch loride (15 mg/kg body weight) subcutaneously daily for 90 days. Control ani mals received equal volumes of normal saline daily for 90 days. Testes were removed at 15, 30, 60, and 90 days after cocaine injection. Tissues were w ashed and homogenized in ice-cold metaphosphoric acid solution or Tris-HCl buffer. Reduced glutathione, glutathione peroxidase, and malonaldehyde leve ls were determined by colorimetric assay. Statistical analysis was performe d using analysis of variance. Results. Testicular reduced glutathione and glutathione peroxidase were sig nificantly decreased in the treatment testes 15, 30, 60, and 90 days after chronic cocaine injection compared with controls (P <0.05). The testicular malonaldehyde level was 20.8% (P <0.05), 22.1% (P <0.05), 31.2% (P <0.05), and 24.7% (P <0.05) above the control value on days 15, 30, 60, and 90, res pectively. Conclusions. Our findings demonstrate that chronic administration of cocain e to male rats induces a depletion of reduced glutathione and glutathione p eroxidase. Adverse effects of cocaine on the testes are at least in part du e to impairment of the function of the antioxidant defense and further enha ncement of lipid peroxidation. UROLOGY 54: 925-928, 1999. (C) 1999, Elsevie r Science Inc.